EXTREMAL OVERALL ELASTIC RESPONSE OF POLYCRYSTALLINE MATERIALS

Polycrystalline materials comprised of grains obtained from a single a nisotropic material are considered in the framework of linear elastici ty. No assumptions on the symmetry of the polycrystal are made. We sub ject the material to independent external strain and stress fields wit h prescribed mean values. We show that the extremal overall elastic re sponse is always achieved by a configuration consisting of a single pr operly oriented crystal. This result is compared to results for isotro pic polycrystals. (C) 1997 Elsevier Science Ltd.